Dopamine has been implicated in numerous neurological disorders. It is generally recognized that either excessive or insufficient functional dopaminergic activity in the central and/or peripheral nervous system may cause hypertension, narcolepsy, and other behavioral, neurological, physiological, and movement disorders including Parkinson's disease, a chronic, progressive disease characterized by an inability to control the voluntary motor system.
A number of ligands for the treatment of dopamine-related dysfunction of the central and peripheral nervous system are described in U.S. Pat. No. 5,047,536 issued Sep. 10, 1991, U.S. Pat. No. 5,420,134 issued May 30, 1995, and International Publication WO 96/02513 published Feb. 1, 1996. Furthermore, International Publication WO 97/06798, published Feb. 27, 1997, describes compounds having the general tetrahydro-1H-napth[1,2,3-de]isoquinoline chemical structure described below.

In particular, International Publication WO 97/06799 specifically describes the synthesis and use of (±)-8,9-dihydroxy-2,3,7,11b-tetrahydro-1H-napth[1,2,3-de]isoquinoline denominated as “dinapsoline” in the description. The synthesis of dinapsoline is depicted generally in FIGS. 1 and 2 as well as in the experimental section. Further description of the synthesis and pharmacological evaluation of dinapsoline is described by D. Ghosh, et al. in J. Med. Chem., Vol. 39, pp. 549–555 (1996).
However, neither publications contains a description of the stereoisomers of dinapsoline or their potential pharmacological behavior. Although there is some speculation that the possible activities may reside in one enantiomer, there are no actual examples or biological data presented.